As I posted recently I jumped into the ancient coin end of the pool. I recently purchased a small lot of 7 unattributed ancient coins. Here is an attempt at identification of one of the coins. The large serpent on the reverse helped with identifying it (I think). Any and all corrections are welcome. I apologize for the hideous photos. Pergamon -Mysia 19 AE 2nd cent. B.C. Laureate head of Asklepios right / serpent cooled around omphalos. BMC 158
I agree-- Pergamon, Asklepios/serpent. I don't have the references and it looks like there are some variations of the reverse so the BMC coin you referenced may or may not be the same as yours.
I did notice there were at least seven or eight variations/ varieties. I also noticed some sources mis-identified the head on the obverse as Zeus.